Performance-Based Aspects and Constructability of Fibrous LMC Overlays

摘要

It is generally accepted that the latex-modified concrete (LMC) overlay is a superior protection system for bridge decks. The incorporated latex acts as a plasticizing agent providing good workability even for low water/cement ratios. When exposed to air, the latex polymerizes forming a membrane around the hydration products resulting in a lower permeability and inherent flexibility to resist freeze and thaw cycles. Nevertheless, the latex imposes constructability limitations that dramatically increase the initial installation cost of the LMC overlay. The latex starts to polymerize within 15-30 minutes dictating the need for mobile mixers to install the LMC overlay. The cost of the latex adds to the cost of the LMC especially when the oil price increases. This paper presents and discusses the effect of different types and combinations of macro and micro synthetic fibers on the major performance characteristics and constructability of the fibrous LMC overlay.